Emissions Explained
How much CO2 are we emitting into the atmosphere? Who emits the most? What is Net-Zero and are we on track to reach it?
In this blog, Part 1 of a new series on Energy & Emissions, we will look at exactly how much CO2 the world produces, which countries produce the most now and which have the biggest historical emissions. We will also look at emission reduction targets, explain the meaning of Net-Zero and investigate whether the pledges from various countries will be enough to reach it.
A number of graphs in this blog are from Our World in Data, a fantastic resource for trustworthy information on emissions and much more. Sources for each graph can be found using the link here.
Global Emissions
Since the industrial revolution, humans have been producing greenhouse gas emissions in huge volumes, tipping a delicate climate balance towards rapid warming. Initially, Europe and the USA produced the most emissions as they were the first fully industrialised regions, but Asia has rapidly caught up and even overtaken the West, and the total global emissions are still rising.
Who emits the most?
Currently, China is the world’s biggest emitter, accounting for over 25% of CO2 emissions. The USA comes in second and the EU (data includes the UK) third. There are also significant contributions from Japan, Russia, Mexico, Canada, Iran, Saudi Arabia, South Korea, South Africa and Brazil. In addition over 3% of CO2 emissions are not attributed to a single country but are caused by international aviation and shipping, a large proportion not covered specifically by the Paris Agreement that will nevertheless need to be reduced.
However, this only shows the current situation, if you look historically, the USA and Europe have emitted the most C02 into the atmosphere over the last 250 years. Since CO2 hangs around in the atmosphere for a very long time (300-1000 years according to NASA.) this historical impact should be taken into account when nations assess who has to do the most to reduce emissions.
When it comes to comparing countries progress on emissions reductions the result vary wildly. The UK has made significant emissions reductions largely thanks to a phase-out of coal power, and Europe and the USA have also reduced their emissions in the last decade due to similar shifts in primary energy supply. However rapidly developing countries that have taken on the majority of the world manufacturing capabilities, such as India and China, have seen a rapid rise in emissions that shows no sign of levelling off, let alone reducing. Meanwhile, fossil fuel producing nations such as Canada, Russia and Australia continue to have increasing emissions, and this, combined with rapidly developing nations in Asia, is causing global emissions to continue to rise.
Absolute vs Per Capita Emissions
When listening to world leaders talk about their emissions reduction targets and actions you might hear nations like China and India mentioning how low their emissions are “per capita”. This simply means per person, and these countries have large populations so their emissions are shared among a large number of people. On the other hand, smaller oil & gas producing countries such as Kuwait and Saudi Arabia have astronomically high emissions per capita due to their small populations and high emissions. The highest per-capita emitters are shown below.
Of course, the climate doesn’t care how we measure emissions, the CO2 is reaching the atmosphere whichever way relative contributions are calculated.
Still, it can be informative to see which countries emit the most per person which is normally an indication of the carbon intensity of their lifestyles, and unsurprisingly there is a strong relationship between income and carbon footprint per person.
What are our emissions targets?
Each nation has its own emissions reduction targets, called a Nationally Determined Contribution (NDC). All countries are being encouraged to produce new or updated NDCs this year in time for COP26.
In April this year the USA hosted a virtual Leaders Climate Summit where it was hoped some nations would improve their emissions reduction targets, the USA, Japan and Canada increased their ambition, while other countries notably did not.
These emissions reduction targets, such as the UK’s promise to reduce emissions 78% by 2035, are all dependent on a baseline that the reduction can be compared to, in this case the year chosen is 1990. Meaning the UK’s emissions will be 78% lower in 2035 than they were in 1990.
Each country uses different baselines, so it can be difficult to compare like for like. Luckily Dr Simon Evans from Carbon Brief has done the maths on the latest pledges promised in the Leaders Climate Summit hosted by the US, shown here.
With kind permission from Dr Simon Evans, Carbon Brief.
What is “Net-Zero”?
One of the most frequently used targets is “Net-Zero”, which simply means all the emissions being produced are balanced by emissions being removed from the atmosphere, leaving a “net” sum of zero emissions being added to the atmosphere. “Cabon neutrality”, as promised by China by 2060, means broadly the same thing, with some potential for more wiggle room over the use of offsets.
Many of these pledges stipulate reaching Net-Zero by 2050. This is because an IPCC report on global warming of 1.5°C said in 2018:
“Limiting warming to 1.5°C implies reaching net zero CO2 emissions globally around 2050 and concurrent deep reductions in emissions of non-CO2 forcers, particularly methane.”
However, the IPCC does not suggest that simply reaching Net-Zero by mid-century is all we need to do, we have to lower emissions rapidly before then as well to have a better chance at keeping the temperature rise to 1.5°C:
“Limiting warming to 1.5°C depends on greenhouse gas (GHG) emissions over the next decades, where lower GHG emissions in 2030 lead to a higher chance of keeping peak warming to 1.5°C.”
Net-Zero targets are not universally welcomed. Some see national Net-Zero targets as too vague, especially if it is not specified whether they refer to CO2 or all greenhouse gases. Net-Zero targets have come in for criticism for being too far-off in the future to spark the reductions needed now, and for an over-reliance on offsets or carbon-absorbing technologies that have yet to be proven at scale.
Their defenders would point out that they signal a big shift in the acceptance among nations that they do have to reduce emissions down to zero at some point, and the hope is that they will cause more and more pressure to reduce emissions sooner. The pledges are also most effective when they are set into law, such as the case in the UK, because then, in theory at least, decisions made by the government should consider whether they are working towards Net-Zero and if they are not they can be in breach of their own laws and held to account more easily. The least effective targets are simply promising to reach Net-Zero, with no intermediate targets and no binding legislation.
You can compare the net-zero promises of each country in this tracker.
Much of the success of COP26 will come down to how many, and which, nations pledge legally binding emissions reduction targets by 2050, and more pressing intermediate targets by 2030.
Will current pledges be enough?
If, and it is a big if, each country reaches their promised emissions reduction goals under the Paris Agreement, will it be enough to make the world Net-Zero?
The answer is no.
There is a very large “emissions gap” and although recent pledges from the US and others have reduced that gap it remains significant, we still need to find a way of reducing our emissions by over 20 Gigatonnes of CO2 by 2030.
Put simply, the world needs to do more to reduce emissions, and fast.